The present invention relates generally to bowling balls and, more particularly, to a new bowling ball having improved pin striking and lane tracking characteristics.
Modern bowling balls generally include a large spherical core which is surrounded and encapsulated by a relatively thin shell having a smooth spherical outer surface. This outer shell, sometimes referred to as the cover stock, may be formed from a variety of materials such as rubber, urethane, plastic, etc.
The composition and nature of the material used to form the cover stock affects the hardness and density of the outer surface of the bowling ball. In one respect, the hardness and density of the outer surface of a ball is important in that, to be approved by the American Bowling Congress (ABC), the cover stock must meet specific standards. A minimum criteria to be approved by the ABC is that the outer surface of the bowling ball must register a hardness of at least 72 Shore Durometer D (Shore D Hardness). As an upper limit the surface of the ball must not exceed 90 Shore D Hardness.
In another respect, the hardness of the outer shell is important in its relation to the balls ability to "track" or adhere to the bowling lanes and its striking power when impacting the bowling pins. Bowling balls with hard outer surfaces impact pins with superior striking force because the harder, denser outer surface does not yield or give upon impact with the pins. This provides better pin-to-pin mixing action which in turn promotes greater pin fall. A problem with these harder, denser balls, however, is that they generally have smoother, slicker outer surfaces, which surfaces have a low coefficient of friction with the lane. Thus, the spin applied to a bowling ball will less likely produce the conventional hooking action desired by the bowler to bring the ball into the pins in the so called "pocket" of the ten pin set-up. Bowling balls with the softer outer shells or cover stocks do provide greater adhesion with the lane, which adhesion allows the ball to hook and drive into the aforementioned "pocket", but the softer surface yields upon impact with the pins and therefore loses the strong pin action required for high pin fall and game scores. The present invention overcomes these and other problems and provides a bowling ball which provides the improved traction and driving action of soft shelled balls while at the same time providing the superior pin striking and pin fall producing capabilities of a ball having a hard dense outer surface.